Belgian biologists and psychologists have determined that the seasons have a greater impact on human mind more than the environment.
So researchers asked 28 volunteers to perform tests for attention and memory at different times of the year. At this time, they monitored the activity of their brain. Each time the volunteers were invited to a lab for 4.5 days prior to the test. Thus, regardless of the season, researchers maintained the same air temperature and light level in a laboratory.

Although the tests were about the same, each brain showed different activity. So, it was the maximum during performing tasks for attention in the summer, and tasks for improving memory – in the fall.
According to this, the researchers concluded that the brain operates differently depending on the time of year. So it tries to compensate the changes in the environment: reducing or increasing the length of daylight, temperature changes and humidity, etc.